Collision detection sensor

Abstract

A sensor that can rapidly and accurately detect a side collision of a vehicle. The sensor includes a fixed member in a vehicle door and a movable member that has an impact receiving part. The impact receiving part has a high rigidity outside of the fixed member. The impact receiving part also has energy absorbing parts with lower rigidity and a detection part arranged opposite to the movable member at a predetermined interval above the fixed member. When the impact receiving part receives an impact exceeding a predetermined valve, the energy absorption parts are deformed so as to move the movable member. This movement is then detected by the detection part.

We claim: 
     
       1. A collision detection sensor comprising: a fixed member fixed in a vehicle door;   a low load operation mechanism in which a pair of detection parts are arranged in parallel formation on a surface of the pressure receiving side of said fixed member and a plurality of elastic members are arranged at a predetermined interval on a surface of a cover body covering said detection parts, and tip ends of said plurality of elastic members alternately face said pair of detection parts through said guiding holes provided at said cover body, and when a vehicle receives an impact force during a collision, more than one pair of said elastic members are elastically deformed and brought into contact with each of said pair of detection parts, whereby said detection parts are actuated; and   a high load operation mechanism that is constituted so that when said cover body receives an impact force exceeding a predetermined value, said cover body is deformed or moved and brought into contact with each of said pair of detection parts, whereby said detection parts are actuated.   
     
     
       2. A collision detection sensor according to claim 1 wherein: said collision detection sensor is provided with a locking member that locks said cover body on said fixed member at a predetermined interval against said pair of detection parts; and   when said cover body receives an impact force exceeding a predetermined value, said movable member is moved so as to shear off said locking member, whereby said sensor is actuated.   
     
     
       3. A collision detection sensor according to claim 1 wherein said pair of detection parts are constituted by comb-shaped electrodes. 
     
     
       4. A collision detection sensor according to claim 3 wherein said pair of detection parts are constituted by two pairs of comb-shaped electrodes arranged opposite each other at a predetermined interval.